Apparatus and method for visualization of myocardial infarct areas and accessory pathways

Abstract

A visualization apparatus includes a storage unit and a computation unit. The storage unit stores a three-dimensional model of a heart, excitation propagation data indicating temporal variations of electrical signal strength in myocardium during propagation of excitation in the heart, and infarct area data indicating locations of infarct areas in the heart. The computation unit places a measurement point on an accessory pathway between the infarct areas. Then based on the excitation propagation data, the computation unit determines a variation range of electrical signal strength as a range between its minimum and maximum values at the measurement point. The computation unit outputs a picture that visualizes propagation of cardiac excitation in the three-dimensional model, based on the excitation propagation data, by varying a visual property in the picture to represent variations of the electric signal strength within the determined variation range.

What is claimed is: 
     
       1. A visualization apparatus comprising:
 a memory configured to store a three-dimensional model of a heart, excitation propagation data, and infarct area data, the excitation propagation data indicating temporal variations of electrical signal strength in myocardium during propagation of excitation in the heart, the infarct area data indicating locations of infarct areas in the heart; and 
 a processor configured to perform a procedure including:
 placing a plurality of points in each of a first infarct area and a second infarct area adjacent thereto, 
 producing a plurality of line segments between the points placed in the first infarct area and the points placed in the second infarct area, 
 placing a measurement point on one of the line segments that is the shortest of all, the measurement point being neither in the first infarct area nor in the second infarct area, 
 determining a variation range of electrical signal strength, based on the excitation propagation data, the variation range being a range between minimum and maximum values of electrical signal strength at the measurement point, and 
 outputting a picture that visualizes propagation of cardiac excitation in the three-dimensional model, based on the excitation propagation data, by varying a visual property in the picture to represent variations of the electric signal strength in myocardium within the determined variation range. 
 
 
     
     
       2. The visualization apparatus according to  claim 1 , wherein the determining a variation range includes:
 obtaining a locus of the measurement point that moves as a result of deformation of the three-dimensional model during a simulated beating motion of the heart; and 
 determining the minimum and maximum values of electrical signal strength on the obtained locus of the measurement point. 
 
     
     
       3. The visualization apparatus according to  claim 1 , wherein the visual property is hue, saturation, value, or any combination thereof. 
     
     
       4. A visualization method comprising:
 placing, by a processor, a plurality of points in each of a first infarct area and a second infarct area adjacent thereto, 
 producing, by the processor, a plurality of line segments between the points placed in the first infarct area and the points placed in the second infarct area, 
 placing, by the processor, a measurement point on one of the line segments that is the shortest of all, the measurement point being neither in the first infarct area nor in the second infarct area; 
 determining, by the processor, a variation range of electrical signal strength, based on excitation propagation data indicating temporal variations of electrical signal strength in myocardium during propagation of excitation in the heart, the variation range being a range between minimum and maximum values of electrical signal strength at the measurement point, and 
 outputting, by the processor, a picture that visualizes propagation of cardiac excitation in the three-dimensional model, based on the excitation propagation data, by varying a visual property in the picture to represent variations of the electric signal strength in myocardium within the determined variation range. 
 
     
     
       5. A non-transitory computer-readable storage medium storing a visualization program, wherein the visualization program causes a computer to perform a procedure comprising:
 placing a plurality of points in each of a first infarct area and a second infarct area adjacent thereto, 
 producing a plurality of line segments between the points placed in the first infarct area and the points placed in the second infarct area, 
 placing a measurement point on one of the line segments that is the shortest of all, the measurement point being neither in the first infarct area nor in the second infarct area; 
 determining a variation range of electrical signal strength, based on excitation propagation data indicating temporal variations of electrical signal strength in myocardium during propagation of excitation in the heart, the variation range being a range between minimum and maximum values of electrical signal strength at the measurement point, and 
 outputting a picture that visualizes propagation of cardiac excitation in the three-dimensional model, based on the excitation propagation data, by varying a visual property in the picture to represent variations of the electric signal strength in myocardium within the determined variation range.